Ferrari driver Sebastian Vettel has said that "Mercedes are the favourites" for the upcoming Japanese Grand Prix.
Vettel was victorious in the Singapore Grand Prix as Lewis Hamilton retired after 33 laps and Nico Rosberg finished fourth.
However, the German doesn't think that Mercedes will encounter similar problems this weekend.
He told BBC Sport: "It was a big surprise to see Mercedes struggling. I don't expect it to be the case here, but if the chance is there we have to go for it.
"We can be reasonably confident. Hopefully we will be a bit stronger again, but Mercedes are the favourites."
Vettel lies in third place in the driver rankings, 49 points behind leader Hamilton.
